A flat-panel CRT display basically consists of an electron-emitting device and a light-emitting device that operate at low internal pressure. The electron-emitting device, commonly referred to as a cathode, contains electron-emissive elements that emit electrons over a wide area. The emitted electrons are directed towards light-emissive elements distributed over a corresponding area in the light-emitting device. Upon being struck by the electrons, the light-emissive elements emit light that produces an image on the viewing surface of the display.
Specifically, the electron-emissive elements are conventionally situated over generally parallel emitter electrodes that are opaque--i.e., impervious to light, typically ultraviolet ("UV") and infrared ("IR") light as well as visible light. In an electron-emitting device that operates according to field-emission principles, control electrodes typically cross over, and are electrically insulated from, the emitter electrodes. A set of electron-emissive elements are electrically coupled to each emitter electrode where it is crossed by one of the control electrodes. The electron-emissive elements are exposed through openings in the control electrodes. When a suitable voltage is applied between a control electrode and an emitter electrode, the control electrode extracts electrons from the associated electron-emissive elements. An anode in the light-emitting device attracts the electrons to the light-emissive elements.
The electron-emitting device in a flat-panel CRT display commonly contains a focusing structure that helps control the trajectories of the electrons so that they largely only strike the intended light-emissive elements. The focusing structure normally extends above the control electrodes. The lateral relationship of the focusing structure to the sets of electronemissive elements is critical to achieving high display performance. In fabricating the electron-emitting device, the opaque nature of the emitter electrodes can present an impediment to achieving the requisite lateral spacing between the focusing structure and the sets of electron-emissive elements. Accordingly, it would be desirable to configure the emitter electrodes in such as way as to facilitate controlling the lateral positions of components, such as the focusing structure, in the electron-emitting device.
Short circuits sometime occur between the control electrodes, on one hand, and the emitter electrodes, on the other hand. The presence of a short circuit can have a very detrimental effect on the display's performance. For example, a short circuit at the crossing between a particular control electrode and a particular emitter electrode can prevent part or all of the set of electron-emissive elements associated with those two electrodes from operating properly. It would also be desirable to have a way for configuring the emitter electrodes to facilitate removal of short-circuit defects.